whats the highest gearing I should use?

[Urgeoner]

Okay right now I'm using the stock 18t mamba monster pinion with a 65t spur on my Revo conversion. It's pretty slow
I was thinking that the gearing is too low and want to step up a little.
It is very hot in Nebraska and humid as well, and I don't want to overheat obviously, and I was thinking of maybe getting a 58t spur and a 22-24t pinion..any help would be great as to what would be an ideal setup.
Oh and I got two of these 2s batteries hooked in series are these good for bashing/racing?
http://aircraft-world.com/shopexd.asp?id=6229

[Urgeoner]

can anyone chime in maybe i should just do 24t because don't know if 22t will reach the sput because its got the e revo tranny. Anyone think thats to much?

[shaunjohnson]

well i run 18/65 gearing on my E-revo for racing conditions and temps stay around the 120 mark on 6s.

so i guess you could try a 20t pinion and move up to a 22t.
basicly play with it till you find a sweet spot.
then after you find the top speed sweet spot i recomend gearing down just a tad to allow you to have a bit of fun (high load acceleration, wheelies etc)

this is all IMO so it's really up to you.
there are many many other more experienced people on this forum who might chime in later on
shaun

[Urgeoner]

thanks Shaun, I run that same gearing right now, but it's too slow because I run only 4s...time to upgrade to 6s? on 6s it will hit about 37.5mph good for racing.

[brushlessboy16]

you say your using the stock MMM pinion with a 65t spur gear? the pinion is not the problem.. put the correct spur gear on it ~40T, and you will notice the difference bigtime.


...Unless your are not running the revo transmission?

[shaunjohnson]

ooohhhh sorry i missed the bit where you said it was a conversion
ok gear it the same as the nitro was, 15t pinion and 40t spur and see how you go, (2200kv on 4s is about the same rpm as the nitro motor)
shaun

[Urgeoner]

thanks problem is I used the erevo brushless tranny and motor mount, so to make a 15t pinion mesh anything smaller than a 68t spur is impossible because the top of the transmission case blocks the motor from being able to drop.
You think I'll burn up some stuff running 22/58?

[suicideneil]

Differential Ratio: 2.8461538461538462
Transmission Ratio: 1.8333333333333332
Other Ratio: 1
Spur Tooth Count: 68
Pinion Tooth Count: 18
Total Voltage: 14.8
Motor KV: 2200
Tire Diameter (inches): 5.9
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0
Spur/Pinion Ratio: 3.78 : 1
Total Ratio: 19.71225 : 1
Tire Circumference (inches): 18.54 inches (470.8 mm)
Total Motor Speed: 32560 RPM
Vehicle Speed: 28.99 mph (46.57 km/h)
Effective KV Value: 2200

29mph, thats really shite given your setup's potential (you have good lipos I assume?)

68/22 = 35mph, much better, but still a little slow.

68/24 = 39mph, much more like it.

If you bumped the voltage upto 5s or 6s, then speeds around 45mph and 50mph would be easily do-able, given good batts.

Just keep an eye on your temps:

180 for the mtor, ideally 140-160.
160 for the esc, ideally 120-140.
120 for the lipos, ideally 100-110.

[Urgeoner]

thanks Neil for the good info.
I got 2 of the 2s: so 4s total:

http://aircraft-world.com/shopexd.asp?id=6229

are these pretty good?

[suicideneil]

Feck yeah, only thing better really would be the 'vx' version of those, but then you get a lower mah capacity for the higher discharge rate/ C rate. You should easily be able to shoot for that 39mph goal with yours, but see how it does with the 35mph setup first (better safe than sorry etc etc).

[shaunjohnson]

oh so you actually did the same conversion i did LOL.
first i thought it was an e-revo, then i thought it was a convert with a nitro tranny and now you tell me it's exactly like mine hahahahaha!!

i run 18/65 gearing (shaved minute amount from tranny) and that is great fearing from 4s right up to 6s for my uses. (racing)

follow what suicide said and you are all green :D
shaun

[Urgeoner]

Thanks Shaun! You said fearing, does that mean using lol..

18/65 on 4s (what I tried) and only get about 25mph!!
on 6s it would be 37.5 mph...
Differential Ratio: 3.3076923076923075
Transmission Ratio: 1.8333333333333333
Other Ratio: 1
Spur Tooth Count: 65
Pinion Tooth Count: 18
Total Voltage: 14.8
Motor KV: 2200
Tire Diameter (inches): 5.65
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0.006
Spur/Pinion Ratio: 3.61 : 1
Total Ratio: 21.89815 : 1
Tire Circumference (inches): 17.75 inches (450.85 mm)
Total Motor Speed: 32560 RPM
Vehicle Speed: 24.99 mph (40.15 km/h)
Effective KV Value: 2200
KT constant: 0.61 oz-in/A
Motor Torque: Amperage not specified...
Final Torque: Amperage not specified...
Final Power: Amperage not specified...

[Urgeoner]

also I run hybridv3 diffs so that eats away at the numbers also